package com.ucpaas.sms.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.lang3.StringUtils;

/**
* TODO 生成验证码
* @author 29p9g02
* @version
 */
public class CheckCodeUtil {

	
	/*该方法主要作用是获得随机生成的颜色*/ 
	@SuppressWarnings("unused")
	private static Color getRandColor(int s,int e){
		Random random=new Random ();
		if(s>255) s=255;
		if(e>255) e=255;
		int r,g,b;
		r=s+random.nextInt(e-s);	//随机生成RGB颜色中的r值
		g=s+random.nextInt(e-s);	//随机生成RGB颜色中的g值
		b=s+random.nextInt(e-s);	//随机生成RGB颜色中的b值
		return new Color(r,g,b);
	}
	
	
	public static void makeCheckCode(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		//设置不缓存图片
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "No-cache");
		response.setDateHeader("Expires", 0);
		//指定生成的响应图片,一定不能缺少这句话,否则错误.
		response.setContentType("image/jpeg");
		int width=86,height=39;		//指定生成验证码的宽度和高度
		BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);	//创建BufferedImage对象,其作用相当于一图片
		Graphics g=image.getGraphics();		//创建Graphics对象,其作用相当于画笔
//		Graphics2D g2d=(Graphics2D)g;		//创建Grapchics2D对象
		Random random=new Random();
		Font mfont=new Font("宋体",Font.BOLD,21);	//定义字体样式
		//g.setColor(getRandColor(200,250));  //背景颜色
		g.fillRect(0, 0, width, height);	//绘制背景
		g.setFont(mfont);					//设置字体
		g.setColor(new Color(73,128,192)); //图片颜色
		g.drawRect(0,0,width-1,height-1); //图片边线
		/*
		for(int i=0;i<50;i++){
			int x=random.nextInt(width-1);
			int y=random.nextInt(height-1);
			int x1=random.nextInt(6)+1;
			int y1=random.nextInt(12)+1;
			BasicStroke bs=new BasicStroke(2f,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);	//定制线条样式
			Line2D line=new Line2D.Double(x,y,x+x1,y+y1);
			g2d.setStroke(bs);
			g2d.draw(line);		//绘制直线
		}*/
		//输出由英文，数字，和中文随机组成的验证文字，具体的组合方式根据生成随机数确定。
		String sRand="";
		String ctmp="";
		int itmp=0;
		//制定输出的验证码为四位
		for(int i=0;i<4;i++){
			switch(random.nextInt(3)){
				case 1:		//生成A-Z的字母
				     itmp=random.nextInt(26)+65;
				     ctmp=String.valueOf((char)itmp);
				     break;
				/*case 2:		//生成汉字
					 String[] rBase={"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"}; 
					 //生成第一位区码
					 int r1=random.nextInt(3)+11;
					 String str_r1=rBase[r1];
					 //生成第二位区码
					 int r2;
					 if(r1==13){
						 r2=random.nextInt(7);	 
					 }else{
						 r2=random.nextInt(16);
					 }
					 String str_r2=rBase[r2];
					 //生成第一位位码
					 int r3=random.nextInt(6)+10;
					 String str_r3=rBase[r3];
					 //生成第二位位码
					 int r4;
					 if(r3==10){
						 r4=random.nextInt(15)+1;
					 }else if(r3==15){
						 r4=random.nextInt(15);
					 }else{
						 r4=random.nextInt(16);
					 }
					 String str_r4=rBase[r4];
					 //将生成的机内码转换为汉字
					 byte[] bytes=new byte[2];
					 //将生成的区码保存到字节数组的第一个元素中
					 String str_12=str_r1+str_r2;
					 int tempLow=Integer.parseInt(str_12, 16);
					 bytes[0]=(byte) tempLow;
					 //将生成的位码保存到字节数组的第二个元素中
					 String str_34=str_r3+str_r4;
					 int tempHigh=Integer.parseInt(str_34, 16);
					 bytes[1]=(byte)tempHigh;
					 ctmp=new String(bytes);
					 break;*/
				default:
					 itmp=random.nextInt(10)+48;
					 ctmp=String.valueOf((char)itmp);
					 break;
			}
			sRand+=ctmp;
//			Color color=new Color(20+random.nextInt(110),20+random.nextInt(110),random.nextInt(110));
//			g.setColor(color);
			//将生成的随机数进行随机缩放并旋转制定角度 PS.建议不要对文字进行缩放与旋转,因为这样图片可能不正常显示
			/*将文字旋转制定角度
			Graphics2D g2d_word=(Graphics2D)g;
			AffineTransform trans=new AffineTransform();
			trans.rotate((45)*3.14/180,15*i+8,7);*/
			/*缩放文字
			float scaleSize=random.nextFloat()+0.8f;
			if(scaleSize>1f) scaleSize=1f;
			trans.scale(scaleSize, scaleSize);
			g2d_word.setTransform(trans);*/
			g.drawString(ctmp, 15*i+15, 25);
		}
		HttpSession session=request.getSession(true);
		session.setAttribute("randCheckCode", sRand);
		g.dispose();	//释放g所占用的系统资源
		ImageIO.write(image,"JPEG",response.getOutputStream());	//输出图片
	}


	/**
	 * 验证是否正确
	 * 
	 * @param request
	 * @return
	 */
	public static boolean check(HttpServletRequest request) {
		String input = request.getParameter("randCheckCode");
		String session = (String) request.getSession(true).getAttribute("randCheckCode");
		if (StringUtils.isNotBlank(session) && StringUtils.isNotBlank(input) && session.trim().equalsIgnoreCase(input.trim())) {
			return true;
		}
		return false;
	}
}
